QoS in Web Caching

Manuel Afonso, Alexandre Santos and Vasco Freitas

Universidade do Minho
Departamento de Informática
P-4700-320 Braga, Portugal

Tel.: +351 253 604475
Fax.: +351 253 604471
E-mail: {alex,vf} (at) di.uminho.pt


Nowadays, hierarchical organisation of caches is commonly used in the WWW, the main objective being to overcome the cumbersome paths of communications among servers by attempting to improve the response times experienced by end-users. The efforts are mostly focused on the still exponentially growing Web. There is an interest in the analysis of different caching architectures using the same basic hardware, software and network setups. In order to evaluate architectural changes, measures of caching server QoS have to be defined.

This paper proposes one such measure based upon a users perception of the response times to his requests. This measure is then used in a case study that analyses and evaluates the QoS of cache servers of an University and of a national network.

Keywords: Web caching architectures, QoS, ICP, HTCP, HTTP.

3rd International WWW Caching Workshop, Manchester, England, Jun 15-17, 1998